X-kay apparatus



Sept. 22, 1953 D. susslN ET Ax.

x-RAY APPARATUS Filed nay 11 195o 3 Sheets-Sheet 1 DAV/D susslN A;

HADEN 5. WARE www ATTORN EYS D. SUSSIN ET AL sept. 22, 1953 X-RAYAPPARATUS 5 Sheets-Sheet 2 Filed May 11 1950 DAV/D sussm s( HADEN s.WARE ATTOR NEYS Sept. 22, 1953 D. SUsslN ET AL X-RAY APPARATUS 3Sheets-Sheet 5 Filed May 1ll 1950 @www ATTOR N EYS Patented Sept. 22,1953 X-RAY APPARATUS David Sussin, South Fort Mitchell, and Haden S.Ware, Fort Mitchell, Ky., assig'nors to Keleket X-Ray Corporation,Cincinnati, hio,.a corporation of Ohio Application May 11, 1950, SerialNo. 161,366

(Cl. Z50-62) 12 claims. l

This invention relates to cassette changers for use in radiography.

The invention has particular relation to devices of this character whichare adapted for use in stereoradiography as well as in making singleradiographs and wherein the cassette holder containing a plurality ofcassettes is mounted to swing with a pendulum motion between twooperative positions for successively aligning the cassettes therein inthe proper exposure position with respect to the patient to takesuccessive radiographs, with the stereoscopic eiect being obtained byshifting the position of the X-ray tube between exposures to change theangular relation of the X-ray beam and the patient in the resulting twopictures of the stereoscopic pair. lt will be apparent, therefore, thatduring stereoradiography there is an interval between the two exposures,and it is desirable that this interval be short, both to assure asnearly as possible that the same internal conditions obtain in bothpictures and also to minimize the time during which the patient isrequired to remain motionless. In addition, it is desirable that theshifting movement of the cassette holder be effected with minimum shockin order to assure that the cassette be motionless during exposure.

The present invention provides a pendulum type cassette changer in whichthis desirable smooth and rapid shifting of the cassette holder isfacilitated by means of a compensating weight carried by the cassetteholder and operated by a motor which shifts the eifective position ofthis weight after each swing of the cassette holder. Further assuranceof this desired operation of the device is provided by an arrangement ofcontrol switches operated by the cassette holder and compensating weightwhich cooperate after shifting of the cassette holder to reset theweight in the proper operating position for the return swing of thecassette holder and which also are effective to prevent movement of thecassette holder except when this weight is in proper position.

The invention also provides for improved operating results with cassettechangers of this character by a simple and effective mountingarrangement for the bucky diaphragm. Instead of requiring physicalremoval of the bucky when its use .is not desired, the bucky is mountedby means of hinged arms so arranged that it can be quickly shifted fromits operating position to a laterally removed inoperative position andvice versa without overbalancing the device as a whole and with- Voutinterfering with the electrical connections to the bucky. In addition,this mounting arrange- 2 ment of the bucky permits the use of acompression band when desired either with or without the bucky to aid inholding the patient properly motionless.

It is accordingly one of the principal objects of the present inventionto provide a pendulum type cassette changer which is rapid and smooth inoperation, which includes automatic controls assuring proper action ofthe cassette holder and preventing premature motion thereof, and whichalso includes a simple mounting for the bucky so that the latter can bequickly and easily moved into and out of operating position as desiredwithout aiecting the electrical connections thereto or the operation ofother parts of the device.

Another object is to provide a pendulum type cassette changer whereinsmooth and rapid shift- -ing of the cassette holder from one exposureposition to the other is effected by means of a motor drivencompensating weight which is shifted following each swing of thecassette holder to the proper position for the return swing of theholder, and wherein controls operated by the cassette holder and thecompensating weight prevent premature movement of either member.

It is also an object of the invention to provide a pendulum type changerwherein the bucky is mounted on the device by means of swinging armswhich permit the bucky to be shifted between its operative andinoperative positions as desired without interfering with thecompression band or other parts of the device and wherein operation ofthe bucky is automatically prevented by movement thereof to itsinoperative position without otherwise interfering with the electricalconnections thereto.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

In the drawings:

Fig. l is a front elevation view, partly broken away, showing a cassettechanger in accordance with the operation and with the bucky in operativeposition;

Fig. 2 is a fragmentary top View showing the structure and operation ofthe mounting for the bucky;

Fig. 3 is a fragmentary section on the line 3-3 of Fig. l showing thecutout switch for the bucky;

Fig. 4 is a fragmentary rear elevational view of the cassette changer;

Figs. 5 and S are fragmentary views on an enlarged scale showingsuccessive positions of the compensating weight for the cassette holderand its associated parts;

Fig. 7 is a fragmentary top view of the com- 5 pensating weight and itsassociated parts; and

Fig, 8 is a wiring diagram.

Referring to the drawings, which illustrate a preferred embodiment ofthe invention, the carriage it which forms the main frame of the locassette changer is supported for vertical movement by a pair of uprightcolumns II having a base I2 provided with leveling screws I3 and adaptedto be secured to the wall by a pair of wall jacks indicatedfragmentarily at I4. The l5 carriage Ulis supported by chains I5 andsprockets l secured to a shaft Il extending between the tops of thecolumns II, and these columns are hoilow to house suitablecounterweights (not shown) at the other ends of the chains I5. The shafti? may carry a sprocket or pulley I8 for driving a correspondingsprocket or pulley on the tube stand to effect raising or lowering ofthe tube head in accordance with the vertical adjustment of the carriageIB. A scale I9 is 25 provided for indicating the vertical position ofthe carriage I0, and the knob 20 operates a lock or brake for holdingthe carriage in adjusted position on columns II.

The exposure position for the patient is de- 30 fined by the front plate22 of the carriage, which is hinged to the carriage at 2l below the chinrest 23 to provide ready access to the interior of the carriage forloading and unloading cassettes. A roll of paper 24 may be provided as35 shown to supply a covering sheet for plate 22 for sanitary purposes.The compression band rolls 25 and 26 are mounted on the front of thecarriage at either side of the plate 22 to sup-l port the compressionband 2l indicated in dotted 40 lines in Fig. 2 for holding the patientat the exposure position, the right-hand compression band rolls 25 beingshown as provided with a crank handle 28.

The bucky assembly includes a casing which 45 houses e. bucky diaphragmof the usual construction and its operating switches and magnets. Thecasing E@ is mounted for swinging movement between the operatingposition aligned m with plate 22 as shown in full lines in Figs. lfm and2 and a laterally removed inoperative position indicated in dotted linesin Fig. 2. The mounting for casing 3l) includes a pair of curved arms SIand 32 hinged to the carriage by means"k oi a shaft 123 journaled in aboss 34 at the back 55 of the carriage and provided with a thrustbearing 3e at the top of the carriage. The shaft 33 is located adjacentone side of the exposure position of the device, and the arms 3l and 32r are pinned to shaft 33 and extend beyond the/(i0 opposite side or theexposure position. The outer ends of these arms are hinged to the casing30 by means of a shaft 3S iournaled in swivel brackets Si secured to theedge of the casing, and av thrust bearing 33 is provided between thelower- 65 most bracket 3l and the arm 32.

This arrangement or" swinging arms supports Y the bucky casing in suchmanner as to permit the casing to be swung from its operating positionto an inoperative position spaced completely away from the exposureposition, as indicated in dotted lines in Fig. 2, thus permitting use ofthe device without the bucky while at the same time supporting the buckyfor quick movement into operating position when desired. This armarrangement has the further advantage of permitting free use of thecompression band 2i bot with and without the bucky, since when the buckyis in operating position, the band can be drawn across the front of itas indicated in Fig. 2, and when the bucky is swung away, it is beyondthe left-hand compression band roll 23 and thus is out of the way of thecompression band itself. A latch lil on the left hand edge of casing 3i]cooperates with a retainer on the carriage to hold the casing inoperating position, and an additional catch and retainer s2 are providedat the opposite edge of the casing, the arrangement being such that thecatch i2 is engaged before the latch fi@ and vice versa.

rhe electrical circuits ior operating the bucky are provided by a pairof cables lid and d5 having plugs (it and di at one end and having theirother ends connected to a terminal strip it (Fig. 8) located in thecarriage behind the cover plate de. Sockets 5d and ti at the or" thecasing 3G are adapted to receive these plugs d@ and lil, and it will benoted that the cables are mounted within the hoilow lower arm and arethus out of the way in both positions of the bucky. Also, Fig. 4 showshow the cables enter the arm 32 adjacent the shaft and emerge adjacentthe shaft 3&3, thus assuring minimum fiexing of the cables as the buckyis swung into and out of its operating position.

The cable Lili is connected with a cutout switch 55 (Figs. 3 and 8) forpreventing operation of the bucky when the casing is in inoperativeposition. This switch is mounted on the web which extends across theback of carriage it, and its switch arm Si? (Fig. 3) extends into a pathof a bolt Si carried by a collar t2 secured to shaft The collar 62 is somounted on shaft 33 that when the casing 3Q is in operating position,the bolt el will engage arm et to move it to the dotted position shownin Fig. 8, and when the casing t@ is swung out of operating position,the bolt Si rotates with shaft i553 and thus releases the switch arm tilfor return to the position shown in full lines in Fig. 8.

The cassette holder of the cassette changer is indicated at 15. Itcomprises a generally rectangular frame forming a pair of side by sidecompartments for receiving the two cassettes indicated at TI, and theupper portion of each compartment is open, having no central strut suchas is shown at 'I8 (Fig. 4), to provide for operation of the device witha phototiming device operating through the cassette and holder ifdesired. A pair of parallel arms and BI forms the pendulum mounting forthe cassette holder,

these arms having their upper ends pvoted to the carriage I0 on thehorizontal pivots 82 and their lower ends pivoted to the lower edge ofthe cassette holder. The latter can thus swing with a pendulum motionbetween the operating position shown in Fig. 4 and a similar operatingposition on the opposite side of center with respect to the carriage, asindicated fragmentarily in Fig. 6, to position the cassettes 7lsuccessively in alignment with the exposure position of the device. Thecarriage is provided with adequate lead shielding at either side of thefront plate 22 to protect the cassettes from accidental exposure whennot in exposure position.

The cassette holder is releasably held in each of its two operatingpositions by a plunger 84 depending from the armature 85 of a tripmagnet 8B having an operating coil 3l, the plunger 84 cooperating withcatch plates 88 on the loweredge of the cassette holder to form Ia latchand the coil being energized through a push button switch 90 at the topof carriage I0. As shown in Fig. 8, the plunger 84 and armature85 areconnected by a link 9| through which extends a rod 92 supporting one endof each of a pair of springs 93 having their opposite ends anchored to abracket 94. Thus when the coil 81 is energized by depression of the pushbutton 90, the plunger 84 will be raised to release the adjacent catchplate 80 and permit the cassette holder to swing towards its otheroperating position.

In order to assure that the cassette holder swing all the way from oneoperating position to the other, the arms 80 and 8| are provided withcompensating weights 95 and 99. The compensating weight 95 is carried byan arm and collar 96 on the pivot 82 for arm 8|, and it is adjustableboth radially and angularly with respect to this pivot to permitadjustment of the swing of cassette holder l5 so that it will compensatefor friction equally in both directions. Adjustment of weight 95 is donewhen initially setting up the device, and thereafter it is iixed in itsproper adjusted position.

'Ihe compensating weight 99 is provided on the arm 80 and is caused toshift from one side of center of the pivot 82 to the other after eachswinging of the cassette holder to provide an offcenter load on thecassette holder during each swing. The weight 99 is carried by an arm|00 driven by a small reversible electric motor |I (Fig. 8) having acover |02, the motor and other parts of this compensating weightassembly being carried by a bracket |03 mounted for swinging movementwith arm 80 on axis 82 below a covering boss |04 on carriage I0. Theweight 99 operates between two limit positions defined by bumpers |05mounted on top of the cover |02 in the path of arm |00.

The motor |0| is actuated in timed relation with the swinging movementof the cassette holder to assure proper resetting of the weight 99 aftereach operation of the cassette holder, and provision is also made forpreventing the cassette holder from moving until the weight 99 is reset.

through one of a pair of microswitches and 2 mounted on the carriage I0just above the compensating weight assembly .as shown in Figs. 5 and 6.The switch arms ||3 and ||4 of these switches are adapted to be engagedby a bolt I5 mounted in the upper side of the weight arm |00, and thenormal position of each of these switch arms when out of engagement withbolt I l5 is as shown in Fig. 8 in full lines for arm ||3 and dottedlines for arm 4.

An additional pair of microswitches and |2| is carried by the bracket|03, and these switches control the direction of rotation of the motor|0|. Thus when both switches are open, which is their normal condition,the motor circuits will be open and the motor will be shut off. Closingof the switch |20 sets the motor for counterclockwi-se rotation asviewed in Fig. '7, when current is supplied to its primary coil |0, andclosing of switch |2| sets the motor for clockwise rotation. Theactuating arms |22 and |23 of the switches are adapted to be alternatelycontacted by abutments on the carriage as the cassette holder swings,each abutment comprising a bracket |24 and bolt |25 lhaving its headpositioned in the path of the adjacent vswitch arm |22 or |23. 'Ihebolts |25 can be readily ad- 6 justed to assure that closing of one orthe'other of the switches |20 and |2| will occur just as the cassetteholder reaches one or the other of its two operating positions.

The wiring diagram in Fig. 8 shows the cooperating action of theseseveral switches in coordinating shifting movement of the compensatingWeight 99 with the swinging movement ofthe cassette changer. The twomain power lines |30 and |3| are connected through fuses |32 with theterminals |33 and |34 of a terminal strip |35 which may be mounted atany convenient location such as at the back of one of the columns andfrom these terminals lines |36 and |31 lead to terminals |38 and |39 onthe terminal strip 48. A line |40 connects the terminal |38 with theterminal |4| of the push button switch 95, and a line |42 runs fromterminal |38 through the primary coil |0 of motor |0| to the terminal|43 of switch ||2. This terminal |43 is connected through switch arm ||4in its normal p0- sition with a line |44 to the terminal |45 of switchand the switch arm 3 of switch is connected through line |46 leading tothe power terminal |39. Thus when both the switch arms ||3 and l |4 arein their normal positions, a circuit will be completed through theprimary coil I0 of motor |0| to operate the motor in the properdirection in accordance with the position of the switches 20 and l2 I.

The switches ill and ||2 have terminals |48 and |49 connected with acommon line |50 leading through the energizing coil Si of trip magnet 86to a line i5! from terminal strip 48 which connects with the switch arm|52 of the push button switch 90. In the normal position of switch arm|52, it is connected with a terminal |53 connected by lines |54 and |55with a terminal |55 on the terminal strip |35. This circuit arrangementprovides that when both the switch farms H3 and 4 are in their normalpositions, the energizing circuit for the magnet 89 will be interruptedat switches Il! and ||2 to prevent release of the plunger 34irrespective of the position of the push button switch 99.

The several switches are shown in Fig. 8 in their relative positionscorresponding to the position of the cassette holder i5 in Figs. 4 and5, with the switch arm l |4 in the full line position resulting fromcontact with the bolt H5 and with the switch arm |23 in its full lineposition resulting from contact with the adjacent bolt |25. When thepush button switch 99 is depressed to change cassettes, the result willbe to complete the energizing circuit for the coil 9i', the circuitrunning from terminal 38 through line |90, terminal Ml, switch arm |52,lines |5| and 59, terminal |559, switch arm H4, line |44, terminal |45,switch arm H3, and line |95. Energizing of the coil 3l causes plunger 84to be raised and to release the catch plate 38, thus permitting thecassette holder to swing from right to left as viewed in Fig. 4. v

As soon as the cassette holder starts to swing, the switch |2| is openedas result of movement of the switch arm 23 away from its actuating bolti135, and similarly the switch arm H4 will be released from the holt H5and will return to its position shown in dotted lines in Fig. 8. As aresult, both of the internal circuits of motor |9 will be open at theswitches |29 and l2l, preventing operation of the motor, and also thecircuit through solenoid coil 3'! will be interrupted at the switchesand H2. Thus while the cassette holder is swinging from one operativeAposi-tienta the other, the motor fli will be prevented vfrom operating,and the compensating weight .99 vwill accordingly remain in properposition to provide the desired off-center load on the cassette holderassuring its full swinging stroke. Also, the immediate deencrgizing ofcoil 81 will result in permitting the plunger t4 to drop under theurging of springs s3 into position for latching engagement with thecatch yplate 88 at the right-hand side of the cassette holder as viewedin Fig- 4 when the cassette holder reaches its other operative position.

As soon as the cassette holder reaches its other operative position, asindicated in Fig. 6, the

Switch arm |22 will be urged by its actuating bolt to the `dotted lineposition shown in Fig. to complete the circuits of the motor iti forclockwise rotation in Fig. 1. since the circuit through the primary coilH53 .of the motor has been energized by the shifting or switch arm H4 toits dotted line position in Fig. 8. Therefore, substantiallysimultaneously with the arrival of the cassette holder at its otheroperating position.. the motor lili will start to swing the compensatingweight to the left as indicated in dotted lines in Fig. '1. At the sametime, since this position of the parts as shown in Fig. 6, 'the boit H5is out of contact with both of Switch arms H3 and H4, the circuitthrough coil 81 will remain interrupted until the weight S9 completesits movement and the bolt i i5 contacts the switch arm H3 to shift it tothe dotted line position in Fig. 8, in which position the circuit to thecoil IIU will be interrupted at switch to stop the motor. Thus until theweight 55 has been completely reset, release of the latch plunger 84 isprevented, and the cassette holder will remain in its left-handposition.

As already pointed out, the cassette changer is frequently used fortaking stereoradiographs, with the tube head being shifted between eX-posures. Fig. 8 shows fragmentarily the trip magnet |55 for effectingshifting of the tube head. The switch |5| in Fig. 8 is ordinarilymounted at the tube stand or other control for remote control operation,the switch |5| serving to complete a circuit through the trip magnet |68and the power terminals |33 and E34. Closing of switch |65 alsocompletes the circuit through solenoid coil 81 to effect shifting or thecassette holder l5 simultaneously with the tube head, and withoutoperating the push button switch 9G. As shown, line |62 connects theswitch |5| with the terminal |55 on terminal strip |35, from which thecircuit to the power terminal |39 is completed through the lines |55 and|54, switch |52, lines 5i and |59, switch arm IN, line |44, switch armH3 and line 46.

Fig. 8 also shows the operating circuits for the bucky and theirinterconnection with the circuits for the tube and cassette holder. rlheeX- posure switch for the tube is shown diagrammatically at 85 asconnected between one of a pair of power lines |66 and |51 and aterminal |68 on the terminal strip |35. A line Hi! leads from terminal|63 to the switch arm Sil of cutout switch 55, and when the arm 6B is inits dotted position in the operative position of the bucky casing asdescribed, the circuit will run through the switch terminal VH, theterminals |12 and |13 of plug 45 and socket 5G respectively, and theline |14 to the energizing coil of the bucky release magnet |15. Aswitch 16 is connected betwee-n the magnet |15 and the socket terminal|11, and the associated plug terminal |18 is Vconnected by aline .|73with .a terminal |8 on terminal strip |35, which is in turn connected tothe other power line |51.

A normally open switch is connected between the line |14 and the socketterminal |55, and the associated plug terminal |81 is connected by theline |88 to a terminal |89 on terminal strip |35 from which a line |99leads tothe timer |9| for the X-ray exposure, the arrangement being suchthat the timer will be set in operation when the circuit |85 is closed.A terminal |52 of the cutout switch A55 is also connected with line |88to provide for short circuiting the bucky when the switch arm 60 is infull line position shown in Fig. 8.

The cable 45 provides the circuits for recocking the bucky followingexposure. A line leads from the power terminal |39 to the terminal |96of plug 41, and from the associated socket terminal |51 a line |528leads through a normally open switch |99 t-o the magnet 20D forrecocking the bucky diaphragm. The magnet circuit is completed throughthe socket terminal 20E, plug terminal 282 and line 253 to the powerterminal |53. An additional line 255 is connected to the line |98between switch |99 and magnet 263, and leads to the socket terminal 255.The associated plug terminal 291 is connected by a line 2&38 with aterminal 2i on the terminal strip |35. This terminal 2|0 may either beconnected with the trip circuit at the control, as indicated at 2|2, toprovide for releasing the trip magnets 86 and |60 simultaneously withthe recocking magnet 253|] to eiect shifting of the cassette holder andtube during recocking of the bucky. If desired, terminal 2m may beconnected directly to terminal |56 to operate the cassette holderindependently of the tube.

These several circuits and switches are so arranged as shown that whenthe exposuretswitch |65 is operated, the circuit will be completedthrough the bucky trip magnet |15 to release the bucky diaphragm for itstravel. The switch |16 is arranged to be released by the bucky diaphragmas it starts to move, thus interrupting the circuit through magnet |15,and simultaneously the switch |85 will be closed as a result of themovement of the diaphragm to complete the actuating circuit to thetimer, thus interlocking the bucky travel with the operation of thetimer. The switch |99 in the recocking circuit is positioned in the pathof the bucky diaphragm in such manner as to be closed by the buckydiaphragm at the limit of its travel, thus completing the actuatingcircuit for the bucky recocking magnet. At. the same time, closing orthe switch |99 completes the circuit through line 205 to terminal 2li),and this in turn completes the operating circuit through the trip magnet|60 for the X-ray tube and the trip magnet 85 for the cassette holder.VAs a result, the cassette holder and tube will both be released in timedrelation with the completion or the exposure, so that they will shifttheir positions for the next picture while the bucky is being recocked.

When it is desired to operate the cassette changer without using thebucky, the casing 3|) is swung into its inoperative position asdescribed, thus releasing the switch arm 6|! of the cutout switch 55 toits full line position in Fig. 8, wherein it short-circuits line |10directly to the terminal |92 on line |88, thus providing for completingthe circuit to the timer independently of the bucky when the switch |65is closed without affecting operation of the cassette holder and eventthe switch 55 should have its arm 60 taped or otherwise held in its fullline position in Fig. V8 to maintain the buck'y in operation forcompletion of the circuit through switch |85 in desired timed relationwith the exposure even when the bucky is not being used for theexposure.

It will accordingly be seen that the present invention provides acassette changer having several highly advantageous structural andoperational features facilitating its use for stereoradiography. Thecompensating weight arrangement as described assures smooth and rapidshifting of the cassette holder between exposures inorder to minimizethe time interval between the taking of the two pictures of astereoscopic pair, and the interlocking arrangement with the operatingcircuits for the bucky is also advantageous in facilitatingspeed ofoperation. IThe mounting of the bucky on the carriage is of materialassistance to the operator in facilitating quick and easy movement ofthe bucky into and out of operating position both for purposes ofloading and unloading the cassettes and also for eliminatingv the buckyfrom the line of exposure when its use is not desired without requiringits physical removal from the carriage for the complete utilization ofthe other parts of the changer.

While the form of apparatus herein described constitutes a preferredembodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes maybe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

l. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, pivot means mounting said cassette holder onsaid frame for swinging with a pendulum motion between two operativepositions to align said compartments alternately with said exposureposition, means for releasably holding said cassette holder in each saidoperative position, a casing adapted to receive a bucky, means hingingsaid casing to said frame for movement between an operating positionaligned with said exposure position and an inoperative position, acompensating weight for said cassette holder, drive means supportingsaid weight for shifting movement between limit positions at either sideof center with respect to said pivot means to provide an off-center loadon said cassette holder assuring swinging thereof from one saidoperative position to the other upon release of said holding means,means operated by said bucky for releasingV said holding means uponcompletion of an exposure, means operated by said cassette holder ateach said operative position thereof for actuating said drive means andfor preventing operation thereof during movement of said cassetteholder, means operated by said compensating weight for preventingrelease of said holding means during said shifting movement of saidweight, andmeans for releasing said holding means independently of' 10said bucky to provide for operation of said cassette holder when saidbucky casing is in said inoperative position.

2. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, pivot means mounting said cassette holder onsaid frame for swinging with apendulum motion between two operativepositions to align said compartments alternatively with said exposureposition, means for releasably holding said cassette holder in each saidoperative position, a casing adapted to receive a bucky, means hingingsaid casing to said frame for movement between an operating positionaligned with said exposure position and an inoperative position, acompensating weight for said cassette holder, drive means supportingsaid weight for shifting movement between limit positions at either sideof center with respect to said pivot means to provide an off-center loadon said cassette holder assuring swinging thereof from one saidoperative position to the other upon release of said holding means,means establishing an operating circuit for said bucky between saidcasing and said frame, means operated by said bucky through said circuitfor releasing said holding means upon completion of an exposure, meansoperated by said cassette holder at each said operative position foractuating said drive means to shift said compensating weight, meansresponsive to movement of said casing from said operative position forinterrupting said circuit when said casing is out of said operatingposition, and means for releasing said holding means independently ofsaid bucky to provide for operation of said cassette holder when saidcasing is out of said operating position.

3. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, pivot means mounting said cassette holder onsaid frame for swinging with a pendulum motion between two operativepositions to align said compartments alternately with said exposureposition, means for releasably holding said cassette holder in each saidoperative position, a casing adapted to receive a bucky, a hollow armhinged between said casing and said frame to support said casing formovement into and out of an operating position aligned with saidexposure position, a compensating weight for said cassette holder, drivemeans supporting said weight for shifting movement between limitpositions at either side of center with respect to said pivot means toprovide an off-center load on said cassette holder, wires supported insaid arm for establishing an operating circuit for said bucky betweensaid casing and said frame, means operated by said bucky through saidcircuit for releasing said holding means upon completion of an exposure,means operated by said cassette holder at each said operative positionthereof for actuating said drive means to shift said compensatingweight, a cutout switch for interrupting said circuit, means operated bysaid bucky casing for operating said switch yto interrupt said circuitin response to movement of said casing from said operating position, andmeans for releasing said holding means independently of said bucky toprovide for operation of said cassette holder when said casing is youtof said operating position.

4. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, means mounting said cassette holder on saidframe for swinging with a pendulum motion between two operativepositions to align said compartments alternately with said exposureposition, means for releasably holding said cassette holder in each saidoperative posi- Ition, a compensating weight carried by said mountingmeans and providing an off-center load on said cassette holder to assureswinging thereof from one said operative position to the other uponrelease of said holding means, means supporting said weight for shiftingmovement with respect to said cassette holder between limit positions ateither side of center of said swinging mounting of said cassette holder,means on said frame operated by said weight for preventing release ofsaid holding means during said shifting movement of said weight, andmeans movable with said cassette holder for preventing said shiftingmovement of said weight during said swinging movement of said cassetteholder.

5. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, means mounting said cassette holder on saidframe for swinging with a pendulum motion between two operativepositions to align said compartments alternately with said exposureposition, means for releasably holding said cassette holder in each saidoperative position, a compensating weight carried by said mounting meansproviding an off-center load on said cassette holder to assure swingingthereof from one said operative position to the other upon release ofsaid holding means, means supporting said weight for shifting movementwith respect to said cassette holder between limit positions at eitherside of center of said swinging mounting of said cassette holder, drivemeans for effecting said movement of said weight, cooperating means foractuating said drive means, said cooperating means including parts onsaid frame and other parts mounted for movement with said cassetteholder for cooperation with tsaid parts on said frame substantiallyimmediately upon arrival of said cassette holder at eachsaid operativeposition thereof, and means on Vsaid frame operated by said weight forpreventing release f said holding means during operation of said drivemeans.

6. A cassette changer comprising a frame providing Van exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, means mountinghsaid cassette holder on saidframe for swingingmwith a pendulum motion between two operativel DQS;tions to align said compartments alternately with said exposureposition, means for releasably holdingY said cassetteholder in eachvsaidhoperative position, a oompensatingweight carried .by said mountingmeans providing an off-center load on said cassette holder to assureswinging thereof from one said operative. position tofthe other uponrelease of said holding means, means supporting said vweight forshifting movement with respect to said cassette holder between limitpo;- sitions at either siderof center of said 'swinging mounting of'said` cassette holder drive means for effecting 4said movement of saidweight, cg.. operating means for vactuating said drive means', saidcooperating means yincluding parts 'on said frame 'and other partsmounted #for movement with said cassette lholderfor cooperation withsaid parts 'on said frame only in said operative positions of saidcassette holder, means operated by said weight for preventing release ofsaid holdingmeans during operation of said drive means, and meansoperated by said weight upon arrival at each said limit position fordiscontinuing said drive means and preventing further operation thereofuntil after the next swinging movement of said cassette holder.

7. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving a'plurality of cassettes, means mounting said cassette holder on saidframe for swinging with a pendulum motion between two operative posi-'-tions to align said compartments alternately with said exposureposition, electrically operated means for releasably holding saidcassette holder in each said operative position, an operating circuitfor said holding means, switch means for effecting opening of saidcircuit to prevent release of said holding means, a compensating weightcarried by said mounting means providing an off-'center loa'd on saidcassette holder to as'- sure swinging movement thereof from one saidoperative position to the other upon release of said holding means,drive means for shifting said weight with respect to said cassetteholder between limit positions at either side of center of said swingingmounting of said cassette holder, means located on said frame foroperation by said weight only in one or th'e other said limit positionthereof to operate said switch means to effect closing of said circuit,additional switch means controlling said 'drive means, and means foroperating said additional switch means to actuate said drive means, saidadditional switch means and said operating means therefor being mountedone on said frame and the other for movement with said casette holder inposition for operation only in one or the other said operative positionof said cassette holder.

8. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, an arm and pivotal mounting on said frame forsupporting said cassette holder for swinging with 'a pendulum motionbetween two operative positions to align said compartments alternatelywith said exposure position, means releasably holding said cassetteholder in each said operative position, a compensating weight forl saidcassette holder, means supporting said weight on said arm for shiftingmovement with respect to Vsaid cassette holder between limit positionsat either side of center of said pivot to assure swinging of saidcassette holder from one said operative position to the other uponrelease of said holding means, drive means for effecting said movementof said weight, cooperating switch means and operating means therefor onsaid arm and said frame for actuating said `drive `means substantiallysimultaneously with arrival of said ycassette holder at each saidoperative position to effect said shifting movement of said weightsubstantially immediately after each said swinging movement of saidcassette holder, and additional switch means and cooperating operatingmeans therefor carried by said Weight and said frame for preventingrelease of said holding means during movement yof said weight. l

9. A cassette changer comprising a fra-monroviding an exposure positionfor the patient, a cassette holder having compartments for receiving apluraiity of cassettes, means mounting said cassette holder on saidframe for shifting movement between two operative positions to alignsaid compartments alternately with said exposure position, a casingadapted to receive a bucky, a pair of extended arms for supporting saidcasing, means hinging one end of each said arm to said frame at one sideof and respectively above and below said exposure position, meanshinging said casing to the other ends of said arms for swinging movementwith said arms between an operating position aligned with said exposureposition and an inoperative position spaced laterally from said exposureposition, said arms extending respectively above and below said casingand being hinged thereto at a position adjacent the opposite side ofsaid exposure from the other ends of said arms in said operativeposition of said casing to provide for free access by the patient tosaid exposure positionwith said casing in said inoperative positionwithout removing said casing from said frame.

10. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, means mounting said cassette holder on saidframe for shifting movement between two operative positions to alignsaid compartments alternately with said exposure position, a casingadapted to receive a bucky, an arm for supporting said casing, meanshinging one end of said arm to said frame, means hinging said casing tothe other end of said arm for swinging movement with said arm between anoperating position aligned with said exposure position and aninoperative position spaced laterally from said exposure position toprovide for free access by the patient to said exposure position withoutremoving said casing from said frame, means establishing an electricalcircuit between said casing and said frame for operating said bucky, andmeans responsive to movement of said casing from said operating positionfor interrupting said circuit to prevent operation of said bucky exceptwhen said casing is in said operating positon.

l1. A cassette changer comprising a frame providing an exposure positionfor the patient, a cassette holder having compartments for receiving aplurality of cassettes, means mounting said cassette holder on saidframe for shifting movement between two operative positions to alignsaid compartments alternately with said exposure position, a casingadapted to receive a bucky, an arm for supporting said casing formovement between an operating position aligned with said exposureposition and an inoperative position spaced laterally from said exposureposition, means hinging one end of said arm to said frame adjacent oneside of said exposure position, and means hinging the other end of saidarm to said casing at a position adjacent the opposite side of saidexposure position in said operative position of said casing to providefor outward and lateral swinging of said casing from said operatingposition to an inoperative position spaced laterally from said operatingposition.

12. A cassette changer comprising a frame providing an exposure positionfor the patient, a

cassette holder having compartments for receiving a plurality ofcassettes, means mounting said cassette holder on said frame forshifting movement between two operative positions to align saidcompartments alternately with said exposure position, a casing adaptedto receive a bucky, an arm for supporting said casing, means hinging oneend of said arm to said frame, means hinging said casing to the otherend of said arm for swinging movement with said arm between an operatingposition aligned with said exposure position and an inoperative positionspaced laterally from said exposure position to provide for free accessby the patient to said exposure position Without removing said casingfrom said frame, Wires establishing an electrical circuit between saidcasing and said frame for operating said bucky, said arm being hollowand having said wires supported therein, and a switch mounted on saidframe for interrupting said circuit in response to said movement of saidcasing to said linoperative position.

DAVID SUSSIN. I-IADEN S. WARE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,622,320 Kelley Mar. 29 1927 2,060,981 Fischer et a1 Nov. 17,1936 2,174,738 Eddy Oct. 3, 1939 2,178,867 Bader et al. Nov. 7, 19392,277,330 Kizaur Mar. 24, 1942 2,327,603 Kizaur Aug. 24, 1943 OTHERREFERENCES G. E. X-Ray Corp. Publication Supplement to Pub. 7B-650 2pages, published Aug. 1941.

